F3 TZR

[jools]

No the small end is/was good - I certainly won't use that again.

It appears that the entire front face just cracked off.

I have ordered a set of 1.0mm oversize Cruisin Image pistons as I had been using those in the race LC for some time without problems.

I still think the problem was over revving. I just notice a bit of skirt jammed in the transfer too !!


Luckily the bore isn't too bad, but it will be taken out with the rebore to remove a slight ovality that was there previously.

This happened last year at the final club round an is the first opportunity I had to strip it down.

[epa police]

My mate bought pistons from them for his RD400 .5 oversize and fitted them and it rattled bad. On inspection the piston was stamped .5 but was way undersize.

[jools]

The rebore will be done when the pistons get here to give them a chance.

Not may other options I've seen around here - not sure if there are any Wossners that fit ??

[jools]

I had a re think today. After cleaning and checking the crankshaft, I considered it still had plenty of life in it. After removing the broken pieces of piston skirt and a thorough blast clean rinse and pressure cleanse with turpentine of the mains and big ends and a visual inspection, its worth the risk in trying it out.

once installed and oiled it spins freely with no tight spots or roughness. I then looked at the cylinder and after tapping out the wedged in piston pieces in the transfer I was surprised to find there were no gouges or scratches on the bore surface.

In the parts draw I found the original genuine 0.5 oversize pistons and after a light hone they were fitted.

I just started her up and she sounds nice and crisp with no vibration or odd noises, so I may just enter it in the next PCRA round to see how she runs. It still has the f3 ignition for now but I will look at trying the OEM CDI as well.

Now to fix the silencer mountings and dry fit the TZ250S fairing.

[mboddy]

Great news Jools. See you at Rd4.

[jools]

Cheers Mark - maybe I should have looked at it a little earlier......

The TZ250S fairing is finally fitted. It took a little longer than anticipated with the front TZ bracket I opted to use causing some mental issues, finally got it to fit with everything clearing ok, although it will need the sides trimming around the gear change lever and a major removal for the lick start. I'm not going to do this last bit as I do have a starter trolley and I think it willmupset the look of the fairing.






It needs a bit of paint, probably some blue speedblocks to complement the rest of the bike, still as it looks now its still better than that scungy black thing eh Mark 

Silencers were drilled & remounted with the nozzles now parallel to the bike.

[mboddy]

Looks good Jools.

The black fairing went to Duncan as part of a 'build your own' TZR250 P6 250 Proddy kit.

[jools]

cheers, I also chopped off the old ignition and clock mounts from the top yoke and tidied it up - I can see the instruments better now.

[TZR1ktF3]

Looks great! Can you post a picture from left and right side at 90 degree angle? I want to see how far the fairing comes back compared to the frame, i have no box starter

[jools]

The bike is in storage at the moment, but when I go down to the lock up I'll take the photos you requested.

It still displayed the same issues during testing so I have pulled the ignition off to send away for testing to eliminate that area.
Changing to a 50/50 fuel mix (Avgas/Unleaded) made no difference either. So it has slipped down the list of prorities for now - plus I'm enjoying the 3XV too much 

[tzr-v4]

You could have your fork tube cut about 50mm and re-threaded for the fork cap.
Then they will come just a the top triple clamp.

I've a picture somewhere of the job done.

[jools]

I heard back from Grant Maguire a few days ago where I have my complete TZR250 F3 ignition being analysed to see if there is any fault - but it appears to be working ok.
The power valves seem to be working as expected too opening around 5500 and fully open by 10,000.
Interesting that he said when shutting off they stay open till revs drop to around 3000 before starting to close. I'm wondering if that is a timing issue - he is not giving it time to respond ? That may account for that hole I'm experiencing - what I really need is a device to show me on the dash what it is doing. Maybe a potentiometer grafted onto the servo motor with some LED's showing its position?

He did question the 0.85 static timing figure and reckons this might be a mis print. He has never come across a figure so retarded and the advance curve he measured will accept a 1.8 static setting without any danger. So I'm going to set this at 1.4 for a start and see what if any improvement there is.

[jools]

I just had another chat to Grant about the 3YL ignitions he is testing, and we spoke about the TZR again. It seems I misunderstood him and that the YPVS closing follows the reverse of the opening process so that's all ok.

I have decided that I will bolt it all back on, make sure the earth to the servo motor is good and if that doesn't work I'll try advancing the static timing to 1.2, then 1.4 etc to see if that solves the issue.

Got a practice day at the Creek on the 11th so will take it for a good set up session. I won't have anything else in one piece to take as the 3XV is "winterised" and at the storage unit.

The Spondon probably won't be back from NZ by then either. If it is I'll put the 250 top end back on with modified pistons and see how it goes.

[old smoker]

Hi Jools hope all is going well.
I looked at the cruising image gear when i started on my project ,and the price looked too good to be true.
I ended up with Mitaka,I believe the guys in thr UK mainly us these, they have done 1300km so far at 11500rpm no problems ,touch wood.
I am looking to change them and the crank at 3000k, I estimate mine is making 65hp.
Also I told Mark I will publish some details of the project ,so will get on with soon.

[EEKNOWS]

I heard back from Grant Maguire a few days ago where I have my complete TZR250 F3 ignition being analysed to see if there is any fault - but it appears to be working ok.
The power valves seem to be working as expected too opening around 5500 and fully open by 10,000.
Interesting that he said when shutting off they stay open till revs drop to around 3000 before starting to close. I'm wondering if that is a timing issue - he is not giving it time to respond ? That may account for that hole I'm experiencing - what I really need is a device to show me on the dash what it is doing. Maybe a potentiometer grafted onto the servo motor with some LED's showing its position?

He did question the 0.85 static timing figure and reckons this might be a mis print. He has never come across a figure so retarded and the advance curve he measured will accept a 1.8 static setting without any danger. So I'm going to set this at 1.4 for a start and see what if any improvement there is.

Geez Jools you like doing it the hard way,just put a programmable ignition on and be done with it